Supervised anti-theft security system for product displays

Abstract

An anti-theft product display system utilizes a command module and a plurality of sensor satellites arranged in a daisy chain configuration. The command module and sensor satellites operate with microprocessors and can be programmed to perform several operating functions. Each sensor satellite can receive up to eight sensors without requiring shunts or terminators for the unused sensor jacks. A data retention system is incorporated into each sensor satellite to prevent the loss of data in the event of power failure to the command module. The sensor is wired so that an alarm will sound if someone attempts to steal product by either disconnecting the sensor, cutting the sensor wire or shorting the system.

What is claimed is: 
     
       1. An computer-controlled anti-theft security system for product displays comprising: a command module having a front panel, a back panel, power supply means for providing power to the system, a sensor satellite connection receptacle and a programmable device, said programmable device including:   (a) a command module micro-processor electrically coupled to said power supply means and said satellite connection receptacle;   (b) a keypad electrically coupled to said command module micro-processor and disposed on said front panel of said command module, to generate user selected operating instructions to said command module micro-processor, the instructions configuring the anti theft security system to operate in a predetermined configuration;   at least one sensor satellite coupled to the satellite receptacle of said command module, said at least one sensor satellite having a satellite input port, a satellite output port, a plurality of sensor connection jacks, and a plurality of status indicators, wherein said satellite input port and said satellite output port connect additional sensor satellites;   a satellite micro-processor electrically coupled to said satellite input port, said satellite output port, said plurality of sensor connection jacks and said plurality of status indicators; and   at least one sensor adapted to be attached to a displayed product and having a four sensor wires for electrically coupling said sensor to one of said plurality of sensor connection jacks, said sensor comprising: (a) a bi-color LED coupled in parallel with a series connection of a resistor and a diode via two of said sensor wires;   (b) a switch coupled in series with a blocking diode via said other two sensor wires; and   (c) a pullup resistor connected in parallel with one of said sensor wires connected to the LED and both of said other two sensor wires,     so that when the sensor is connected to the command module via the sensor satellite, the command module detects the presence of said sensor and wherein when said switch is closed, said LED indicates a secured state and wherein cutting or short circuiting said wires or opening said switch causes said LED to indicate an unsecure state.   
     
     
       2. A computer-controlled anti-theft security system according to claim 1, wherein said power supply means comprises: a power jack disposed on the back panel of said command module;   a DC power supply releasably connected to said power jack and adapted to provide DC power to said command module; and   a backup power supply for maintaining the operation of the security system when said DC power supply fails.   
     
     
       3. A computer-controlled anti-theft security system according to claim 2, wherein said command module further comprises: a plurality of indicator lights corresponding to each of said at least one sensor satellites connected to said command module, said plurality of indicator lights controlled by said command module micro-processor;   an on/off keyswitch adapted to activate and deactivate the security system;   a speaker adapted to provide audible alarm sounds during operation of the system, said speaker being controlled by said command module micro-processor;   an AC power indicator adapted to provide power status indication to the user, said AC power indicator controlled by said command module micro-processor; and   a backup power supply indicator adapted to provide status of the backup power supply.   
     
     
       4. A computer controlled anti-theft security system according to claim 3, wherein said indicator lights are LED lamps. 
     
     
       5. A computer controlled anti-theft security system according to claim 3, wherein said on/off keyswitch will reinitialize the command module micro-processor and thus reset the system after the alarm goes off provided no sensor alarm state exists. 
     
     
       6. A computer-controlled anti-theft security system according to claim 3, wherein the removal of any sensor or disconnection of any satellite module will be sensed by said command module microprocessor to trip the alarm on said command module. 
     
     
       7. The anti-theft security system according to claim 1, wherein said at least one sensor satellite further comprises: a speaker coupled to said satellite microprocessor and being adapted to selectively provide an audible alarm; and   a local reset button coupled to said satellite microprocessor and being adapted to selectively reset said sensor satellite after an alarm condition, said local reset button being activated or deactivated by said programmable device of said command module.   
     
     
       8. A computer controlled anti-theft security system according to claim 1, wherein said satellite microprocessor is adapted to receive input data from said sensors and generate output data representative of the current operating status of said sensor satellite and any sensor satellites additionally connected to said satellite input port regardless of the presence of said sensor in said sensor connection jack. 
     
     
       9. A computer-controlled anti-theft security system according to claim 8, wherein said satellite microprocessor further comprises: means for receiving from said additionally connected satellites binary input dat wherein 0 represents ground and 1 represents an elevated state;   means for examining said binary input data;   means for generating binary output data in the form of 32 bits (four 8-bit bytes) representative of the current operating status of said sensor satellite and any sensor satellites additionally connected to said satellite input port regardless of the presence of said sensor in said sensor connection jack, and   means for transmitting said binary output data to either another said sensor satellite micro-processor or said command module micro-processor.   
     
     
       10. A computer controlled anti-theft security system according to claim 9, wherein said satellite microprocessor further comprises: means for calculating a parity bit of said binary output data for each byte added,   means for checking said parity bit of said binary input data,   means for waiting and accepting additional binary input data in the event said parity bit signals an error, and   means for transmitting said parity bit with said binary output data.   
     
     
       11. A computer-controlled anti-theft security system according to claim 1, wherein said at least one sensor satellite comprises up to 10 satellite modules coupled in series with each other. 
     
     
       12. A computer-controlled anti-theft security system according to claim 1, wherein each satellite module has up to 8 sensor connection jacks for receiving up to 8 sensors. 
     
     
       13. A computer-controlled anti-theft security system according to claim 1, wherein the keypad is adapted to activate and deactivate said computer-controlled anti-theft security system. 
     
     
       14. A computer-controlled anti-theft security system according to claim 1, wherein a keyswitch activates said keypad to permit the user to generate user selected operating instructions to said command module microprocessor. 
     
     
       15. A computer-controlled anti-theft security system according to claim 1, wherein a battery is electrically connected to said sensor satellites to maintain functionality when said sensor satellite is disconnected from said command module while activated. 
     
     
       16. A computer controlled anti-theft security system according to claim 1, wherein said at least one sensor further comprises: a housing having an interior space, an outer surface and at least one aperture in said outer surface;   a plunger on the switch, said plunger extending through said aperture beyond said outer surface; and   attachment means for securing said housing to a displayed product such that said switch is in a secure state.